Do in-app purchasing providers like Zong, Paypal, and Boku violate iPhone and Android terms and conditions?

I know there are questions posted elsewhere about how to implement in-app purchases on iPhone and Android, but none answer the legality of the solutions today. At the time of release, there was some dispute over whether some of these s开发者_如何学运维olutions violate terms of service, but it's now several months later. There are also now several exceptions like Amazon, which seem to circumvent iTunes for purchases.

Anyone have a definitive answer?

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It seems that the App Store has two main rules when it comes to in-app purchases (IAP):

1. Buying physical goods or services outside the app using the in-app purchase API is not allowed
2. Using something other than the in-app purchase API to purchase content, functionality, or services in an app is not allowed

Amazon is Ok on both these, but I don't know enough about the Zong, Paypal or Boku apps.